Sure, no problem. I’m only able to upload images thru here so here’s a screenshot of what we’re seeing in the viewer (the red text is a note I put in) and here is a link to download the .pptx:Example PowerPoint

Thanks for providing the problematic document. We are able to reproduce your reported issue with version 17.8.0 of GroupDocs.Viewer for .NET. However, the issue is fixed in the later versions (17.9 and greater) of the API (see output). We recommend you to please upgrade the API to the latest version to get rid of this issue.